Thank you for your replies, Anita and Inky.

Regarding the questions you asked, Anita:
1. I feel like he said these things just to convince me to break up with him. He was being himself all the time, but must have felt bothered by me asking him for more attention and to spend more time with me. In other words, because I started to make “demands”, I wasn’t comfortable enough for him anymore. I asked him why he never asked me how I was or what I was doing, and he just replied he would feel stressed if he had to ask me all the time. When we were friends I never complained or asked him to care more about me, and was very much invested in making him feel comfortable around me. He said that this easy-going, open, and uncomplicated me was the girl he had fallen in love with, and not the sad girl who felt lonely all the time and asked him for more care. He accused me of having tricked him and that the girl he fell in love with didn’t exist after all and I had just been playing a role. That hit me very hard 🙁
The main problem he referred to was me not telling him immediately that I felt lonely and withdrew myself, expecting him to make a step towards me instead. I apologized for this and told him it was a bad habit of mine that I wanted to fix and would surely be able to get over it. But he just said “judging by my experience the same thing is only going to happen again and again. this is not something that can be fixed”. Apart from that, my biggest issue with him was that I was never his priority and like I already wrote several times, that he made me feel lonely a lot.

2. my biggest mistake was definitely putting my ex on a pedestal. I literally did anything for him and always put my own interests behind his. I gave him all of my love and care and was always there for him. When I was hurt or sad, I hid my feelings from him, worried that he might get upset and stop liking me. I was very careful around him and worried a lot about what he thought about me in general. I definitely lacked self-esteem and confidence and whatever I did, I always thought about my ex before I even thought of myself. I really loved him more than myself and I realize now that was a huge mistake. So in my future relationships, I know that I need to put my needs at least on the same level as my partner’s, and also I need a partner who regularly shows me that he cares about me and makes me his priority.

@Inky

I will definitely give the “Why NOT me?” method a try! Thanks for the good tip 🙂 I rationally know that I don’t need to get into a new relationship and I truly think my life is wonderful and amazing without a partner, too. However, since I don’t have any big career goals or other aspirations and my priority in life has always been friendships and relationships with other people, the only real goal I have is to experience a warm, stable, and loving relationship with a wonderful guy.
I guess I just want to experience true love and know what it feels like to be loved back. Right now my ex might still be on my mind too much, but as soon as I feel ready for it, I will follow your advice and put myself out there, not expecting anything and just see what happens 🙂 thank you so much!